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This paper presents the derivation of a general wave dispersion relation for warm magnetized plasma under the two-fluid formalism. The discussion is quite general except for the assumption of low frequency and slow phase speed, for which the displacement current is negligible, under the implicit assumption that the plasma is sufficiently dense to satisfy the condition ω p e > ω c e , where ωpe and ωce denote the plasma oscillation frequency and electron gyro frequency, respectively. The present discussion does not invoke charge neutrality associated with the fluctuations although it is implicitly satisfied. The resulting dispersion relation that includes the fluid thermal effects shows that there are three eigen modes, which include those corresponding to ideal MHD, namely, fast, slow, and kinetic Alfvén waves, as well as higher-frequency modes including the ion and electron cyclotron and lower-hybrid resonances. The fluid effects in the ideal MHD wave branches are influenced by the finite Larmor radius scales, and when the wave number in the cross field direction is comparable to these values, the fluid effects become significant. It is found that the Larmor radius should be interpreted in the sense as ion-acoustic gyro-radius instead of ion thermal gyro radius only. That is, it is found that the electrons also contribute to the non-ideal effect associated with the kinetic Alfvén wave. A comprehensive explanation of the polarization of each mode is also presented. The present findings indicate that the polarity may change its sign only for the kinetic Alfvén mode branch and that such a transition is based on the propagation angle. When such a change does take place, it is found that the kinetic Alfvén wave transits to an ion-acoustic mode. For each branch, it is also found that the electric field along the ambient magnetic field is purely transverse. [ABSTRACT FROM AUTHOR]

An experimental setup to fabricate atomic vapor cells for atom spin gyroscope application, containing 87Rb, 129Xe, 131Xe, N2, and H2, is described. The setup comprises a high-vacuum chamber, an 87Rb ampule, a glass cell, gas lines, and a turbopump. First, the glass cell is baked for a week at 450 °C to reduce outgassing from the inner walls of the glass cell. Next, rubidium atoms are evaporated into the cubic glass cell. Then, the cubic glass cell is cooled to 2 °C to increase the amount of 87Rb in the cubic glass cell while the vacuum chamber is heated to 100 °C. 6 Torr of 129Xe, 48 Torr of 131Xe, 140 Torr of N2, and 24 Torr of H2 are injected into the cubic glass cell. The sealing method employs pinch-off glass welding. The transverse spin relaxation times of 129Xe and 131Xe at a magnetic field of 6.2 µT applied to the quantization axis are measured to be 8.1 and 16.5 s, respectively, at a cell temperature of 96 °C using nuclear magnetic resonance spectroscopy. The pressure ratio between 129Xe and 131Xe is determined by comparing the output signals from our atom spin gyroscope. The signal-to-noise ratios are 2500 for 129Xe and 3333 for 131Xe, respectively, and the expected angular random walk of the atom spin gyroscope is 0.062°/h1/2 with a 1-Hz repetition rate. [ABSTRACT FROM AUTHOR]

Entropy production (EP) is a fundamental quantity useful for understanding irreversible process. In stochastic thermodynamics, EP is more evident in probability density functions of trajectories of a particle in the state space. Here, inspired by a previous result that complex networks can serve as state spaces, we consider a data packet transport problem on complex networks. EP is generated owing to the complexity of pathways as the packet travels back and forth between two nodes along the same pathway. The total EPs are exactly enumerated along all possible shortest paths between every pair of nodes, and the functional form of the EP distribution is proposed based on our numerical results. We confirm that the EP distribution satisfies the detailed and integral fluctuation theorems. Our results should be pedagogically helpful for understanding trajectory-dependent EP in stochastic processes and exploring nonequilibrium fluctuations associated with the entanglement of dividing and merging among the shortest pathways in complex networks. [ABSTRACT FROM AUTHOR]

A self-consistent electrostatic odd-symmetric eigenmode (OEM) is analytically found in a solitary type Bernstein-Greene-Kruskal (BGK) equilibrium. The frequency of the OEM is order of the electron bounce frequency and it is spatially odd-symmetric with the scale comparable to that of the solitary BGK equilibrium structure. Such an OEM is consistent with the recent observation from particle-in-cell simulation of the solitary wave [Dokgo et al., Phys. Plasmas 23, 092107 (2016)]. The mode can be driven unstable by trapped electrons within the hole structure of the solitary wave. Such a low frequency, pure electron mode, which may possibly interact resonantly with the ion acoustic mode, provides a possible damping mechanism of the BGK equilibrium. [ABSTRACT FROM AUTHOR]

Electrostatic fluctuations near upper-hybrid frequency, which are sometimes accompanied by multiple-harmonic electron cyclotron frequency bands above and below the upper-hybrid frequency, are common occurrences in the Earth's radiation belt, as revealed through the twin Van Allen Probe spacecrafts. It is customary to use the upper-hybrid emissions for estimating the background electron density, which in turn can be used to determine the plasmapause locations, but the role of hot electrons in generating such fluctuations has not been discussed in detail. The present paper carries out detailed analyses of data from the Waves instrument, which is part of the Electric and Magnetic Field Instrument Suite and Integrated Science suite onboard the Van Allen Probes. Combined with the theoretical calculation, it is shown that the peak intensity associated with the upper-hybrid fluctuations might be predominantly determined by tenuous but hot electrons and that denser cold background electrons do not seem to contribute much to the peak intensity. This finding shows that upper-hybrid fluctuations detected during quiet time are not only useful for the determination of the background cold electron density but also contain information on the ambient hot electrons population as well. [ABSTRACT FROM AUTHOR]

A possible formation of an electron hole structure associated with an obliquely propagating solitary kinetic Alfvén wave (SKAW) in a strongly magnetized plasma is discussed. It is found that transverse electric field along the magnetic field plays a key role in the electron phase space hole formation. Owing to the presence of trapped electrons, SKAW can propagate in both super-Alfvénic and sub-Alfvénic regimes with different spatial structures. In particular, in the sub- Alfvénic case, the density perturbation possesses a dip at the center accompanied by a pair of humps at the edges. Such a feature may be relevant to satellite observation of solitary structures in the Earth's geomagnetic tail region. [ABSTRACT FROM AUTHOR]

Presents a study that analyzed the diffusion of different dislocations in a face-centered cubic crystal. Methodology; Information on a model of self-diffusion; Analysis of the ratio of mobility to diffusivity.

The perpendicular heating and acceleration of ions by linearly polarized Alfvén wave, which is propagating along constant background magnetic field, is studied. The perpendicular diffusion coefficient of ions is calculated through the autocorrelation function based on linear perturbation theory, which unambiguously demonstrates that ion heating is attained by non-resonant wave-particle interaction. It is found that the perpendicular heating and acceleration of ions occur by the Alfvén wave during a relatively short time interval, i.e., approximately 20 ion gyro period (Ωi0t) even though the perturbation amplitude is quite low. Also, it is shown that the temperature anisotropy of ions A, A, where A = T⊥/T∥ − 1, increases with the increasing perturbation amplitude while the parallel ion heating does not occur. Test particle simulation is also carried out in order to investigate the non-resonant perpendicular heating process. [ABSTRACT FROM AUTHOR]

The diffusion of electrons via a linearly polarized, growing electromagnetic (EM) wave propagating along a uniform magnetic field is investigated. The diffusion of electrons that interact with the growing EM wave is investigated through the autocorrelation function of the parallel electron acceleration in several tens of electron gyration timescales, which is a relatively short time compared with the bounce time of electrons between two mirror points in Earth's radiation belts. Furthermore, the pitch-angle diffusion coefficient is derived for the resonant and non-resonant electrons, and the effect of the wave growth on the electron diffusion is discussed. The results can be applied to other problems related to local acceleration or the heating of electrons in space plasmas, such as in the radiation belts. [ABSTRACT FROM AUTHOR]

Particle simulations and a pseudopotential method were used to study ion-acoustic solitary waves in a plasma composed of Boltzmann electrons and kinetic beam ions. Pseudopotential theory was first applied to determine how ion-acoustic solitary waves can exist in a two-component plasma. Then, particle simulations were carried out, wherein ion-acoustic solitary waves were excited by modulating the bias grid voltage in a double plasma model. For the modulation, the potential of the grid bias was rapidly decreased, such that hump-type ion-acoustic solitary waves with good Gaussian shape were excited one after another, forming a train of waves. The simulation also showed that the phase velocities of ions decrease sharply when the solitary wave occurs, which indicates that the solitary ion-acoustic wave is excited via the inverse Landau damping process. [ABSTRACT FROM AUTHOR]

Effects of dust charges on the nonlinear ion acoustic solitary waves in a fully relativistic dusty plasma for both cases of negative and positive dusts are numerically studied based on the pseudopotential method. In the presence of dusty particles, it is found that various types of nonlinear acoustic waves exist in forms which can be viewed as sequential combinations of three kinds of elementary solitary waves: bump, dip, and kink-type solitary waves. The number and the sequence of the constituent elementary solitary waves in a given nonlinear waves depend more sensitively on dust particle density than any other parameters. For negatively charged dust particles of low density, the nonlinear wave is in the shape of bumpy solitary wave. For a somewhat higher density, the wave changes into a form which can be viewed as a combination of bump and dip-type solitary waves. As the density is increased further, a more complex nonlinear wave composed of bump, kink, and dip-type solitary waves emerges. For a much higher density of dust particle, the nonlinear wave can have a shape that can be considered as a combination of bump and kink-type solitary waves. For the case of positively charged dust particles, two kinds of nonlinear waves can exist: bump-type solitary wave and a combination of bump and kink solitary waves. For both cases of negative and positive dust particles, it is found that single dip-type solitary wave does not exist. It is also found that as dust particle density increases, the signature of the elementary waves becomes less prominent. [ABSTRACT FROM AUTHOR]

The nonlinear solitary Alfvén wave in a magnetized dusty plasma with a low β assumption, obliquely propagating to an external magnetic field, is investigated based on the Sagdeev potential. It is found that there exists a double layer solution as well as the compressive solitary Alfvén waves. It is shown that the amplitude of the compressive and rarefactive solitary Alfvén waves decreases with a dust charge density, whereas that of the double layer behaves in the opposite way. In addition, it is found that the speed of the solitary Alfvén wave is independent of the dust charge density. [ABSTRACT FROM AUTHOR]

Effects of the isothermal ion pressure on the dust ion acoustic solitary waves (DIASWs) in a dusty plasma, which are obliquely propagating to an external magnetic field, are investigated based on the Sagdeev potential. It is found that as the ion temperature increases the speed of the DIASW increases. The increase is more effective for a higher value of the directional cosine lz. The small amplitude solutions of the Sagdeev potential Ψ(n) expanded up to δn3 and δn4, as was done in the previous study [Choi et al., Phys. Plasmas 12, 022304 (2005)], exhibit different behaviors with respect to the change in the ion temperature. The width and height of a double layer are found to decrease with the increase in the ion temperature for both the small and the large amplitude solutions. [ABSTRACT FROM AUTHOR]

The nonlinear ion acoustic solitary wave in a magnetized dusty plasma, obliquely propagating to the embedding external magnetic field, is revisited. It is found that when the charge density of dust particles is high, the Sagdeev potential needs to be expanded up to δn4 near n=1. In this case, it is shown that there could exist rarefactive ion acoustic solitary waves as well as the kink-type double layer solutions, in addition to the conventional hump-type ones found in the δn3 expansion. The amplitude variations of ion acoustic solitary waves in a magnetized dusty plasma are also examined with respect to the change of the dust charge density and the wave directional angle. [ABSTRACT FROM AUTHOR]

Asymmetric magnetic reconnection with a non-zero By component is studied using a three-dimensional magnetohydrodynamic simulation and the results are interpreted in terms of the dayside reconnection at the magnetopause. The B[sub y] component is implemented by rotating the magnetosheath field. It is seen that a magnetic bulge is formed in the magnetosheath region but displaced in the y direction due to the tilted magnetic field line geometry of reconnection. The bulge moves away from the reconnection region along the magnetopause with a speed significantly slower than that of the symmetric case. In fact, the reconnection rate is seen much slower than the symmetric case. It is also seen that the reconnection rate decreases as the angle of rotation increases. The discontinuity associated with magnetic reconnection geometry is identified as a slow shock with Alfvén waves attached to it on the magnetospheric side, while on the magnetosheath side an intermediate shock is seen, which evolves into a slow shock and a rotational discontinuity near the center of the bulge and near the y-directional edges of the current disruption region. A large B[sub y] component is generated on the open field lines, exceeding the initial sheath By near the center of the bulge. The inflow mass flux into the reconnection region from the magnetosheath is seven times larger than that from the magnetosphere in the present study, while the outflow mass flux into the magnetosphere is five times larger than that into the magnetosheath, implying that a significant mass transfer occurs from the magnetosheath into the magnetosphere. The outflow plasmas move mostly along the magnetic field lines in the downstream and transported toward the polar region. [ABSTRACT FROM AUTHOR]

Three-dimensional magnetohydrodynamic (MHD) simulations are carried out in order to study the interaction of upstream density pulses with the planetary bow shock. In this work, three distinguished types of the density pulse have been simulated: (1) Pure density pulse with no variations in all other variables, (2) density pulse in fast/slow mode-like type, and (3) another pure density pulse with a much stronger peak. For the first case, where the peak density is two times the background value, its interaction with the bow shock results in various MHD waves and a shock in the magnetosheath, including the fast mode wave which evolves into a fast shock, the entropy wave, and the slow mode wave. For the second case, the amplitude of the transmitted density pulse in the magnetosheath is reduced overall as compared to that in the first case. This is due to the generation of the stronger fast mode wave in the magnetosheath, and the effect is more pronounced for the fast mode-like pulse than for the slow mode-like pulse. When the third type pulse is incident with the peak density being five times the background value, the magnetosheath is more strongly compressed, which is followed by an expansion due to the sunward repulsion and then a second compression again. This still results in similar MHD waves and a shock in the magnetosheath, but they are generated in manners well-distinguished from the previous two cases. Based on the results from all three cases, it is suggested that the density amplitude and the properties of its related waves/shock in the magnetosheath can appear quite different depending on the observing spacecraft’s position, and thus necessitating a multispacecraft measurement for a reliable monitor. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this paper, the thermal stability of TiN metal gate with various composition prepared by different preparation technology [(e.g., atomic layer deposition (ALD) or physical vapor deposition (PVD)] on HfO2 high-K dielectric is investigated and compared by physical and electrical analysis. After annealing of the TiN/HfO2 stack at 1000 °C for 30 s, it is observed that: (1) Nitrogen tends to out-diffuse from TiN for all the samples; (2) Oxygen from the interfacial layer (IL) between HfO2 and Si tends to diffuse toward TiN. PVD Ti-rich TiN shows a wider oxygen distribution in the gate stack, and a thinner IL than the N-rich sample. Ti penetration into HfO2 is also observed in the Ti-rich sample, which can potentially lead to the dielectric break-down. Besides, the oxygen out-diffusion can be significantly suppressed for ALD TiN compared to the PVD TiN samples. [ABSTRACT FROM AUTHOR]

The article presents a response by the authors to the comments on their article "Effects of charged dust particles on nonlinear ion acoustic solitary waves in a relativistic plasma," published in a 2009 issue. The authors agree with the critics' argument of on the infinite passage time in strictly mathematical point of view. However, the authors says that the pseudopotential theory cannot explain the solitary wave.

The dependence of the gate tunneling current (Jg) on nitrogen profile (N profile) within an ultrathin silicon oxynitride film is reported. It was found that gate tunneling current is dependent on N profile, even with equal oxide thickness and nitrogen dosage. Gate tunneling current increased with steeper N profile, and it had higher sensitivity for p-type metal-oxide-semiconductor field-effect transistor (MOSFET) than n-type MOSFET. A direct tunneling model based on Wentzel-Kramers-Brillouin approximation has been proposed. The model described the influence of N profiles on gate tunneling current through local change of dielectric constant, band bending, and effective mass. Also, it reasonably explained the different Jg sensitivity in n-/p-MOSFETs, a phenomenon that has not been addressed in earlier publications. [ABSTRACT FROM AUTHOR]

Examines the resistive wall mode in rotating plasma with multiple walls. Identification of the outer wall as active coils for feedback stabilization; Impact of plasma rotation on feedback stabilization; Role of the fake-rotating coil feedback scheme in the establishment of the stability of the plasma rotation.

The acceleration of protons is investigated by tracing their trajectories in the electric and magnetic fields obtained from a three-dimensional magnetohydrodynamic simulation of local magnetic reconnection. The magnetic reconnection is induced by imposing a localized anomalous resistivity in two different initial configurations, the first one without a B[sub y] component and the second with a positive B[sub y] superimposed in the two-dimensional Harris field lying in the xz plane. Applying the trajectory calculations to the geotail condition, the previously published results have been mostly recovered for the B[sub y]=0 case. For the nonzero B[sub y] case, remarkable asymmetry about the z=0 plane appears in the trajectories, and the pitch angle and spatial dependencies of energy gain. For the particles found above the z=0 plane at the earthward edge from the X-line, results are similar to those in the B[sub y]=0 case, while they are quite different for the particles found below the z=0 plane. The trajectories of the particles exiting the simulation domain below the z=0 plane are much more complicated than those of the particles exiting above the z=0 plane. Consequently, the duskward skewness of the energy gain, which is well defined above the z=0 plane, is no longer a general and robust feature below the z=0 plane. It is expected that this up–down asymmetry appears not only in the geotail condition but also in other systems as long as the symmetry about the reconnection current sheet plane breaks down by the presence of B[sub y], i.e., the magnetic field component aligned with the X-line. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]